This invention relates to sealing members, and more particularly, sealing members employed in expansion joints which are disposed in grooves formed in adjacent pavement blocks or other structural elements.
In the construction of highways, bridges, architectural concourses, airport runways and the like in which pavement sections or slabs of concrete or other paving materials are used, provision must be made for the expansion and contraction of such sections due to variations of temperature. Conventionally, grooves are provided between adjacent pavement sections to accommodate the expansion and contraction thereof, such grooves being sealed to preclude the entry of liquids and solid materials therein and to prevent such foreign matter from passing through the grooves and beneath the pavements. These grooves are often sealed by means of hollow, resilient, elastic strips or seals which can be compressed and expanded in accordance with the expansion and contraction of the pavement material.
Often, these seals are provided with internal supporting truss structures comprising a plurality of ribs and crossbars defining numerous spaces or openings therebetween to accommodate folding of the ribs and bars during compression and such seals are enjoying increased acceptance for many purposes. However, the desirability of maintaining the pressure profile across the vertical height of the seal sidewalls substantially level or equal at all points therealong has been recognized. Such desirability is particularly apparent in a low pressure type of seal which is designed to exert a minimum pressure on the joint sides while still maintaining an effective seal.